Anisotropic strains, metal-insulator transition, and magnetoresistance of La0.7_{0.7}Ca0.3_{0.3}MnO3_{3} films

Thin films of perovskite manganite La$_{0.7}$Ca$_{0.3}$MnO$_{3}$ were grown epitaxially on various substrates by either the pulsed laser deposition method or laser molecular beam epitaxy. The substrates change both the volume and symmetry of the unit cell of the films. It is revealed that the symmetry as well as the volume of the unit cell have strong influence on the metal-insulator transition temperature and the size of magnetoresistance.Comment: 6 pages, 3 figure

Nanoscale Prediction of Graphite Surface Erosion by Highly Energetic Gas - Molecular Dynamics Simulation -

This paper was presented at the 4th Micro and Nano Flows Conference (MNF2014), which was held at University College, London, UK. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute, ASME Press, LCN London Centre for Nanotechnology, UCL University College London, UCL Engineering, the International NanoScience Community, www.nanopaprika.eu.In order to understand the fundamental essence in the erosion of graphite by hot gas molecules, in this study we investigate the mechanical properties of a single layer of graphite (e.g. graphene) and the bombardment of CO2 and H2O on graphene at high temperature by using extensive molecular dynamics (MD) simulations. The Reactive Empirical Bond Order (REBO) potential is employed to model the C-C bonds. The stress-strain curve shows that the stiffness of graphene decreases with increase in temperature. The strength of graphene at 2400 K is 60% less than the strength of graphene at 300 K. Also, we observe that the collision with CO2 and H2O provokes the bond breaking of C-C bonds in graphene at high temperature. The bombardment of gas molecules is carried out for different temperatures ranging between 300 K and 3000 K. Until 2400 K, both H2O and CO2 molecules are reflected back from the surface. However, at a critical temperature i.e., 2700 K and beyond, the bombardment of gas molecules breaks the C-C bond in the graphene. As the temperature increases, the graphene is destroyed quickly. This study shows that even the real gas molecules can induce the fracture of graphene at high temperature

Effect of additives on the viscosity of liquid-phase dimethylaluminum hydride

The effect of additives on the viscosity of liquid-phase dimethylaluminum hydride (DMAH) was investigated. The viscosity of pure liquid DMAH was measured to be 6400 centipoise (cP) and due to its high viscosity, it is difficult to vaporize DMAH effectively in a bubbler in the chemical vapor deposition of aluminum. N,N-Dimethyl-1-naphthylamine and N-ethyl-N-methylaniline were selected as an additive because they are a liquid at room temperature and have a high boiling point. The viscosity of DMAH was drastically reduced down to 6 cP with the addition of 3.2 mol % of N-ethyl-N-methylaniline and 8 cP with the addition of 4.3 mol % of N,N-dimethyl-1-naphthylamine.ope

Similarities in Dielectrophoretic and Electrophoretic Trap

This paper was presented at the 4th Micro and Nano Flows Conference (MNF2014), which was held at University College, London, UK. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute, ASME Press, LCN London Centre for Nanotechnology, UCL University College London, UCL Engineering, the International NanoScience Community, www.nanopaprika.eu.In this study we present a universal theoretical formulation of the particle motions in electrophoretic and dielectrophoretic traps. It is extended from the well-known Mathieu equation based theories for Paul trap. The white noise random force model is utilized to form the Brownian motion of particle in the traps and the instantaneous dielectrophoretic force is employed rather than the time-averaged ponderomotive expression. The new approach enables many interesting properties of dielectrophoretic traps about stability and random motion. This study will be expected to provide a concrete protocol for the design of nanoscale traps which is essential in single molecule analysis

Impact crashworthiness of a floating offshore nuclear power plant hull structure in a terrorist attack with an aircraft strike

The aim of this study is to investigate the impact crashworthiness of a floating offshore nuclear power plant hull structure in an aircraft strike; the hull has a double-sided design that includes ballasting with either sand or concrete. As a hazardous event associated with a terrorist attack, one of the unfavourable impact scenarios is adopted in which a Boeing 777 airplane strikes the hull structure at a full speed. This study examines the contribution of ballasting materials such as sand or concrete to the penetration of the striking body into the hull structure in an aircraft strike as the power plant is gravity based sitting on the seabed. The LS-DYNA nonlinear finite-element method is employed for the structural crashworthiness analysis. Details of the computational modelling and resulting insights are documented

Parental influence on children's home computer use and digital divide in education

Session C6: ICCE Conference on Technology, Pedagogy and Education - Full Papers: C6_F9_284FThis case study compares the data from two secondary schools and attempts to contribute to a better understanding of the construct of parental influence on children's information and communication technology use at home. It identifies five components of parental influence: parents' information and communication technology (ICT) skills, parental monitoring, parental control, parental guidance and parental worries. The relationships among these components were often complex with intriguing similarities and differences among the participants. The findings suggest the existence of certain inequalities in education or, as the authors prefer to call it, the digital divide in education.postprintThe 19th International Conference on Computers in Education (ICCE 2011), Chiang Mai, Thailand, 28 November-2 December 2011. In Proceedings of the 19th ICCE, 2011, p. 595-60